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Re: [Xen-devel] PATCH: Actually make /local/domain/$DOMID readonly to th

To: "Daniel P. Berrange" <berrange@xxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] PATCH: Actually make /local/domain/$DOMID readonly to the guest
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Thu, 18 Dec 2008 17:21:10 +0000
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Thread-topic: [Xen-devel] PATCH: Actually make /local/domain/$DOMID readonly to the guest
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On 18/12/2008 15:53, "Daniel P. Berrange" <berrange@xxxxxxxxxx> wrote:

> Explicitly give Dom0 permissions on the /local/domain/$DOMID so it
> becomes the owner of the path. The guest is then granted read perm
> on the path.

Thanks Daniel, that's a nasty one!

However there are other places in xend that commit the same error, and this
interface weakness would doubtless bite us again in future. Hence the patch
I actually committed (c/s 18933) actually takes a different strategy: in the
bowels of the xend xenstore C package I check to see if the caller is try to
change permissions of the node owner, and if so I fudge in dom0 as the owner
instead. A bit grim, but I think probably a safer bet in this instance.

What do you think of it? If it seems okay I will backport and will have to
do new RCs of 3.2.3 and 3.3.1.

 Thanks again,

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